The repeat tasks only show the first instance. On one hand, it's proper because you'd not work on the next instance after completing the first instance. However, if you wanted to see your commitments over time, you'd not see the long list of repeated instances.

I suppose a work-around would be to create Monday prep task and repeat weekly, then create a Wednesday prep task and repeat that weekly too. This would keep both days showing a week ahead.

Or, if you really want all the tasks, use the "add multiple tasks" option and change the dates of each instance after they're created. (Or create one task, and use the "clone" option... but that would take longer than "add multiple.")